Traditional sound producing (hearing aids and earphones) and hearing protective (earplugs and musician plugs) devices generally require: (1) that the device provides a good acoustic seal which is important for device performance and sound quality, and (2) that the device fits comfortably in the ear. Existing methods take many forms with one being the focus of the discussion here—the use of ear domes or ear tips that fit inside the ear and connect to an external electronic device. This method of adapting sound producing devices to the ear through the use of pre-molded ear domes or ear tips is common. This concept is common to everything from hearing aids to off-the-shelf earplugs to common mp3 ear buds.
It is generally known to use digital processes to manufacture hearing devices. These devices typically include a molded canal portion having a custom shape that conforms to the contours of the ear canal. Such devices, however, are typically rigid and are unable to extend to a sufficient depth within the canal to create a good acoustic seal. Accordingly, such devices can be uncomfortable to wear, provide inferior performance and can become easily dislodged or break when the wearer moves his head or jaw.
As an alternate to utilizing a molded canal member, hearing devices can instead incorporate an ear dome attached or secured to an audio output device. In such devices, the ear dome is traditionally a separate unit from the speaker or sound producing device. Thus, it is not connected on the molecular level to the main housing of the earphone and has the disadvantage of requiring mechanical coupling, adhesives or both. The “coupled” dome design is an older concept in that it does not take advantage of the current digital nature of earmold production. Accordingly, dome designs used in known hearing devices are not custom molded to conform to the actual size or shape of the ear.